PURPOSE: To finely disperse the special carbide precipitated in cladding by welding layer by plastic-deforming the composite material, which forms the cladding by welding layer of specified composition on the outer circumference of low alloy steel core material, with use of V shape anvil in the specified temp. range.
CONSTITUTION: On the outer circumference of a tough low alloy steel core material, the alloy cladding by welding layer, which has a composition consisting of, by weight, 1.2-2.9% C, 0.2-2.5% Si, 0.25-1.0% Mn, 0.25-1.75% Ni, 3.0-21.0% Cr, as essential components, also, containing one or more kinds among 0.25-6.5% Mo, 1.0-6.5% W, 1.0-5.5% V and having the balance Fe, is formed. This composite material is forged to a roll shape in the range of 1000-1200°C with use of V shape anvil having 120-140° vertical angle so that the alloy cladding by welding layer is subjected to plastic deformation. By this forging, the grain refining and uniform dispersion of special carbide in cladding by welding layer is attained. Also, the boundary between cladding by welding layer is strengthened.
SATO YUICHIRO
SEO YOSHITOSHI
YAMAMOTO ATSUO
SAITO HIROMICHI
FUJIKO KK